What is 600medley mean in swimming?

Answer 1

Individual Medley (abbreviated to Medley or IM) is when a swimmmer swims butterfly, backstroke, breaststroke and freestyle (in that order) in the same race. So 100m medley in a 25m pool would be one length on each stroke. Official medley events incllude 100m (25m on each storke) 200m (50m on each stroke) , and 400m (100m on each stroke)individual medley (200m and 400m olympic events).

600 medley is not an event that officially exists but it would comprise of: 150m butterfly, 150m backstroke, 150m breaststroke and 150m freestly (in that order) continuosly.